Screw jack



5mm III? 1924.

5. R. DEE

SCREW JACK 3 Sheets-Sheet 1 Filed Sept. 50. 1921 AW R a J k W 5W mm MN \NN QW \NNNW NM 0M m mw .mw n W hm v ML Ham aw i 0 mm MMJQMWW 4, W e RNQ, mm (A Q 1m mm NW aw QY 2 V NY a NW N a $5 iimu WM Kw WWW W imam w p 1924.

S R. DEE

' SCREW JACK Filed Sept. 30.

1921 3 Sheets-Sheet 2 wwfg mm m, 1924. 1,473

5. R. DEE

SCREW JACK Filed Sept. 30. 1921 s Sheets-She 5 nearer srnon a, man, or cmceoo, rumors.

SCREW JACK.

- Application filed September 30, 1921. Serial No. 504,407.

To all whom it may concern:

Be it known that I, SIMON R. DEE, a citizen of the United States, residing at Chicago, in the county of Cook and State of Illinois, have invented certain new and useful Improvements in Screw Jacks, of which the following is a specification.

This invention relates to a jack having a, work transmitting rod which is reciprocated longitudinally through the medium of screw threads, and. particularly to that type of screw jacks in which the range of movement.

'of the work transmitting rod is multiplied by applying simultaneous longitudinal movement to the member in which the work transmitting rod is threaded, as, for instance, by constructing said member in the form of a sleeve which is itself threaded in the mounting for the jack and is positively rotated in its mounting as well as upon the rod.

One ob'ect of the invention is to provide a simplifie construction of screw jack of the class described, as well as an improved'driving mechanism therefor, and to this end, one feature of the invention consists in providing for the threaded sleeve a drivingwheel which surrounds the sleeve coaxially and has driving connection therewith without restricting the longitudinal movement of the sleeve; the driving wheel being confined axially in the mounting of the sleeve and being'itself driven through suitable speed reduction gearin so that as the driving wheel is rotated, t e sleeve will be fed longitudinally by its threaded connection with its mounting and carry the working rod wlth 1t, and at the same time will feed the working rod relatively to the sleeve by reason of the threaded connection of the rod and sleeve and the projection of a pin transversely from the worknig rod and into a groove of the mounting for retention of the rod against rotation.

Another object is to render the jack self arresting upon the attainment of its limit of movement in either direction; and to this end, a further feature consists in arranging a system of pull and thrust connections, whereby one of the longitudinally reciprocating screw actuated members, or, if desired, either of said members, or both of them, can im art the throw to the reversing clutch; a su ordinate feature incident to this part of the preferred embodiment of the invention consisting in locating a clutch rod coaxially with the working rod and in a bore formed in the latter so as to receive therefrom, alternately, a thrust and a ull as the workin rod reaches the limits 0 its movement, an arranging suitable leverconnections between this clutch rod andxthe clutch; and still another subordinate feature incident to this part of the preferred embodlment of the invention consists in utilizmg for the clutch body the same transmitting connections as are employed for controlling the clutch by hand.

The screw jack herein described is adapted for performing work upon a truck or vehicle upon which it may be mounted, as, for instance, the work of movingthe vehicle a limited distance from an obstacle which it may encounter, such as a road depression or obstruction that cannot be overcome by the normal propelling power of the vehicle; and, to this end, a flexible connector is applied to the end of the working screw and suitably guided in a direction that adapts it to be passed beyond the confines of the vehicle and attached to a fixed object or anchorage, against which the jack can-pull in moving the vehicle.

In the accompanying drawings- Figure 1 is a longitudinal axial section of a screw jack embodying the features of the present invention which are, immediately concerned with the construction of the jack.

Figure 2 is a transverse section on the line 2*2* of Figure 1.

Fi ure 2* is a sectionon the line 2 of Figure 1.

Figure 3 is a side elevation of a motor vehicle illustrating one use to which the jack may be put. a

Figure 4 is a view similar to Fi re 3 showing another use to which the jac may be put; and

Figure 5 is a side elevation showing the jack embodied in a form adapted to serve the purposes of an ordinary portable lifting jack.

Referring to Figures 1, 2, and 2 6 rep resents the working rod adapted to erform work, as, for instance, by provi ing it with eye 7 to which may be attached a flexible cable or other connector. is constructed with threads 8 and adapted to be driven in the direction of its longitudinal axis by relative rotation between the rod and a correspondingly threaded sleeve 9 surrounding it, which is similarly provided This rod c llO with threads 10 working in the correspondingly threaded mounting 11. Longitudinal movement of the rod 6 is developed by rotating the sleeve 9, while the rod is held stationary by some suitable means, such, for instance, as a cross pin 12 traveling in the guideways 13, and by such rotation of the sleeve 9 not only is the rod 6 fed longitudinally and relatively to the sleeve, but the sleeve also moves longitudinally in the mounting 11 and correspondingly amplifies the movement of the rod by carrying the rod with it at the same time that it is thrustin the rod ahead of it.

n order to rotate the sleeve 9 and still leave it free to move longitudinally, adrive wheel 14: is fitted coaxially upon the sleeve and enters into driving connection with the latter through means of a key 15 working in the longitudinal key-way 16 of the sleeve, the wheel being confined against axial movement during such rotation, by its confining housing 11 formed with the mounting 11. Wheel 14 is driven by small pinion 17 on a shaft 18 that is in turn driven by a clutch member 19 which is adapted to interengagewith either of two clutch members 20, 21, which are constantly driven by the bevel pinion 22 on a power shaft 23. Clutch member 19 is controlled by fork 24 mounted on rock shaft 2/1 and embracing the clutch member 19, and a crankarm 25 on the outer end of said rock shaft, connected through link 26 to the crank lever 27 which is fulcrumed at 28 and adapted to be manually controlled by a handle 29.

With the construction thus far described, and assuming that rotation is being imparted to the shaft 23, it is simply necessary to move the handle 29 to throw the clutch 19 into mesh with one or the other of the oppositely rotated clutch members 20 and 21, when a longitudinal movement will be imparted to the working rod 6 which is equivalent to the combined feeding movements of the screws 8 and 10. If the handle 29 be moved in one direction, the rod 6 will be fed outward, and if the handle be moved in the other direction the rod will be fed inward.

In order to prevent the feed ofi the rod 6 from over-runningits limit, particularly when the shaft 23 is running continuously, the lever 27 is provided with an automatic clutch rod 30 that is provided with one or more shoulders through which it is adapted to encounter a longitudinally reciprocating member, for instance, the shoulder provided in the collar. 31 which is in the path of the end 32 of the sleeve 9, the shoulder 33 on rod 30 which is on one side of the head 3-1 in the bore 35 of the rod 6, or the shoulder 37 which is on the inner end of the clutch rod 30 adapted to be encountered by the inner face of said head 34. Clutch rod 30 is preferably provided with a displaceable locking dog 38 adapted to drop into either of the seats 39 and hold the red at its respective limits of movement.

The mounting 11 is preferably divided in the medial plane of the housing 11 to facilitate assembly around rod 6, sleeve 9, and drive wheel 14, and has its members united by tie bolts 40 or uivalent means. For introduction of the pin 12 into screw 6, the removable plug 41 is provided, and for as sembly of the shaft 18, clutch members 19, 20, 21. and driving gear 22, the housing ll may be provided with a separable cap 11 removably secured in position by screws 11".

A screw jack of the character described is adapted for various uses, some of which are herein suggested. For instance, the jack may occupy the position shown at 11 in Figure 3, where the eye 7 of rod 6 is connected by flexible connector 42 with the arm {13 of a crank lever 44 that is adapted to raise the dumping body 45 upon its rear pintle 46. Or, as shown in Figure 4, the jack occupying the position 11 may be connected with a flexible cable 42 guided around sheaves 47, 48, 49, to a point beyond the rear confines of the vehicle, or past the pulleys 48--49 to a point beyond the forward confines of thevehicle, and there provided with a hook 50 or other anchoring or engaging means, so that the jack may be utilized to pull the vehicle beyond an obstruction, or to slide a hea package up an inclined tailboard into the liody 15.

The lifting lever 13, 44 may be present in the arrangement of Figure 4 just as in Figure 3, means being provided for holding the cable t2 out of the way of the cable 42 while the latter is being used, as, for instance, by detaching the hook 42 of the working rod 6 before inserting the hook 42, and then hanging the cable 42 in the sling 42 and engaging its hook over the pin 42. I As shown in Figure 5, the casing 11, 11, 11 may beprovided with a supporting base 1.1? and an engaging'head 7 for an axle I or other element to be lifted, and thereby adapted to serve as a portable lifting jack.

Siaft 23 will be driven by power connection, such, for instance, as that provided by bevel gear connection 51, 52 with the power shaft 53 of motor vehicle as suggested in Figure 3, or by a sprocket chain 54 which will receive an ordinary; pull chain, as suggested in Figure 5.

I claim:

1. In a screw jack, a longitudinally reciprocating screw, a drive wheel therefor, a shaft actuating said drive wheel, a reversing clutch for driving said shaft, actuating connections for said clutch, and means for controlling said actuating connections comprising a lon 'tudinally movable member extending su stantially parallel to the screw and having a part lying in the path of and encountered by the latter, as it nears the limit of its movement.

2. In a screw jack, a longitudinall re ciprocating screw, a drive wheel there or, a shaft actuating said drive wheel, a reversing clutch for driving said shaft, actuating connections for said clutch, and means for controlling said actuating connections comprising a longitudinally movable member extending coaxially into the screw and having shoulders within and Without the screw, that are engaged by the screw as it nears the limits of its movements.

3. In a screw jack, arecipro'cating worktransmitting screw, a pin projecting trans versely from said screw, a housing surrounding said work-transmitting screw and having a groove paralleling the same, in which the end of said pin travels during the reciprocation of the screw, a tubular screw I internally threaded to said work-transmitting screw and having external threads through which it is both fed and supported' in the housing, and means for rotating the tubular screw relatively to both the housing and the work-transmitting screw.

4. In a screw jack, a housing constructed with an internal feeding thread, a tubular screw having external threads fitted to said feeding thread, a driving wheel confined against axial movement in" said housing, surroundin said tubular screw and adapted to rotate the same without restricting its longitudinal movement, a work-transmitting screw threaded to the interior of said tubular screw, an extension on the housing beyond the threads of the housing which receive the tubular screw, said extension surrounding a portion of the Work-transmitting screw between its outer end and the' threads through which it engages the tubu- SIMON n. DEE. 

